I. Field of the Invention
This invention relates generally to instruments to be used during the performance of a laparoscopic cholecystectomy procedure, and more particularly to an instrument for carrying out a laparoscopic cholangiogram.
II. Discussion of the Prior Art
Fairly recently, with the introduction of improved laparoscopes, allowing the viewing of a surgical site on video screens, and the development of improved dissecting instruments, including electrocautery and laser instruments, laparoscopy has become a more popular procedure. Rather than making a long incision through the abdominal wall, surgical operations are conducted through small puncture sites in the anterior abdominal wall. Surgeons have used laparoscopic techniques to evaluate tumors, lyse adhesions and conduct biopsies on internal organs. Because the laparoscopy obviates the need for large incisions made through the abdominal muscles, procedures that once required hospitalization for a week or more can now be performed on an out-patient basis.
Relatively recently, laparoscopy has been used in performing cholecystectomy surgery. Here, a video guidance tube is inserted through an incision in the navel and the gallbladder is removed through three other tiny incisions made in the upper abdomen. More particularly, in carrying out such surgery, a small 2-3 cm skin incision is placed just below the umbilicus to allow passage of a 11 mm trocar that will house the diagnostic laparoscope. This site is ideal because the peritoneum is firmly attached to the fascia and skin. Hence, it is less likely that a properitoneal insufflation will take place.
Next, a Veress needle is passed through the abdominal wall and used to insufflate the abdomen with CO.sub.2. This gas is introduced to a pressure of about 14 mm Hg which distends the abdomen and increases the surgical working space. Once the 11 mm trocar is introduced, the diagnostic laparoscope is placed and the additional puncture sites are made under direct vision while looking at a video monitor. The additional puncture sites allow grasping tools and dissection instruments to be inserted into the abdominal cavity.
Before the gallbladder is excised, it is good practice to do a cholangiogram to exclude the presence of choledocholithiasis so that an endoscopic retrograde cholangiopancreatography with sphincterotomy and stone extraction can take place before the laparoscopic cholecystectomy procedure continues.
In accordance with the prior art, a cut is made through the wall of the cystic duct, followed by the insertion of an ovarian aspiration needle through that incision and the injection of a contrast fluid, such as HYPAQUE.RTM., through that needle and into the duct. Once the cystic duct and surrounding anatomy has been explored fluoroscopically, the dissection of the cystic duct, the cystic artery and the gallbladder itself can proceed.
The present invention is concerned with an improved instrument for performing a laparoscopic cholangiogram and it has the advantage of not requiring plural instrument exchanges to accomplish the procedure. Rather than using a scalpel, scissors or other instrument to first cut into the cystic duct and then replacing the cutting instrument with an ovarian needle as in the prior art, the instrument of the present invention is capable of being clamped at its distal end to the exterior wall of the cystic duct with a needle-like probe penetrating through the wall for allowing the radiopaque fluid to be injected therein. It remains secure until the cholangiogram has been completed and obviates the somewhat difficult procedure of locating a previously made incision with the distal end of an ovarian needle. Moreover, the prior art ovarian needle is not self-anchoring and, as a result, it can lose its purchase relative to the small incision that had been made in a cystic duct.